The present invention relates to an electronic testing apparatus which can, for instance, be adapted to test the function and performance of an artificial satellite station for affirmation on the ground.
It is generally known that a conventional testing apparatus for an artificial satellite station as described, for example, in the article entitled "ETS-1; ISS Checkout Apparatus" to be found in Mitsubishi Denki Gihoo (Mitsubishi Electric Technical Periodical) Vol. 47, No. 3, 1973, comprises, as generally shown in FIG. 12, subsystem test units for testing subsystem by subsystem a satellite station to be tested, and a data processing unit for the processing of data from these subsystem test units. This drawing diagrammatically shows an artificial satellite station designated by reference numeral 1 which is tested from the ground in connection with the function and performance thereof, a series of subsystem testing units 2 for testing in terms of each of the subsystems that comprise the satellite station such items as, for example, the power source for supplying each subsystem with electric power, the control subsystems for controlling the attitude and/or the orbit of the satellite, etc., and a data processing unit 3.
More specifically, each of the subsystem testing units 2 is adapted to perform a test on the ground to check whether the subsystems of the satellite station for the power supply system, the telemetry/command system, the attitude and orbit control system, the propulsion system, the heat control system and the like are operating properly as designed.
In the function test conducted on, for example, a test subsystem for the attitude and orbit control system, a test is undertaken to ensure that its designed ability for attitude control is operating properly through tests on such elements as attitude detection sensors, attitude control electric circuits, attitude control drive mechanisms, etc. Similarly, during the performance test, a test is conducted to check whether the accuracy of attitude control and of control velocity comes within the range of the design parameters.
All data output from the tests on each subsystem as noted above will then be supplied to the data processing unit 3. This data processing unit 3 incorporates testing data processing means based on suitable software which is specifically adapted to undertake data processing and/or editing of the test data output. The output data obtained from the test conducted on, for instance, the attitude and orbit control subsystem, such as analog data including voltage values indicating the data output by the attitude detection sensor and electric current and voltage values observed at many points of the electric circuits, etc., are input together with binary digital data indicating the current ON/OFF status of each switch, binary digital data on the revolution numbers indicating the current control velocity and the like to the above-mentioned data processing unit 3, where the data are subjected to processing and/or editing as noted above. In general, the data processing unit 3 may be a general purpose large-sized computer or minicomputer, and all the data output from this unit may be processed and/or edited by way of binary digital representation.
More specifically, the nature of this data processing unit 3 provided for data processing and/or editing is principally that binary data is converted into decimal digits by virtue of the engineering system of the units, various data collected at certain points in time are classified to be shown in tables, and the behavior of data on variable values is edited to be represented in graphs. Once such data has been processed and/or edited in this manner it may then be output by way of a line printer or a cathode ray tube (CRT) in a visual form.
With such data made available in this manner, specialists in the artificial satellite field may readily perform a diagnostic review of the thus-prepared data obtained from the tests. This diagnostic review of the test data allows a decision to be made as to whether or not the function and performance of each of the functional subsystems incorporated in an artificial satellite station is in a good condition in accordance with the overall design, and the data employed in the system design may be adapted to be employed as the criteria for this determination. In addition, when the test data fails to satisfy the requirements of the system design, a prediction regarding which part of a subsystem is out of order can be made by taking account of precedents and/or technical knowledge related thereto.
Conventional test apparatus used for artificial satellite stations are generally constructed in the manner noted above, and the diagnostic review of the test data obtained on each subsystem of a satellite is in practice done by humans. Thus, it is left to specialists in the artificial satellite field to determine whether or not test data are satisfactory and to predict which part is out of order when appropriate.
It is common practice for engineers or designers of an artificial satellite station to make a trade-off or compromise in regard to the allocation of functions or performance at the design and engineering stages as between the functions and performance essential for a subsystem incorporated in the overall system and a construction that is sufficiently practical to be employed in actuality. For this purpose, functional block diagrams may be prepared. In the conventional design of test apparatus for satellite stations, while it has been common for a trade-off of this type to be made when considering the various design data that could be used in the original design, means of preparing the necessary functional block diagrams have not been incorporated in the design system by way of readily available software. In this connection, all the steps of reviewing the design and engineering stages which involve reexamining the results of implementing a certain design and identifying unsuitable features that need to be corrected have been left to the personnel concerned, and there has been no means available in the conventional test apparatus allowing such design reviews to be undertaken by way of software for the purpose of dispensing with the need for human effort in this work. More specifically, since no means has been adopted capable of making use of such software as the so-called "Failure Mode and Effect Analysis" which is adopted at the time of system design, these steps have to be taken by humans, which naturally means that efficient utilization of the design data cannot be ensured.
As discussed above, the design of conventional artificial satellite test apparatus having the construction noted above involves the diagnostic review of an enormous amount of test data by humans which has required that many specialists in the artificial satellite field have been employed in such diagnostic work. Consequently, a significant problem has been that, owing to the man hours involved in the diagnostic review of such a vast amount of test data, it takes a substantial time for the specialists to complete these tasks in comparison with the completion of the original design drawings and design and engineering data. In order to determine if the test data are satisfactory, to predict the location of any possible defective parts in the system, and to complete similar work, many specialists have been required to expend many man hours. Moreover, since such design and testing work have not been operatively coordinated as the various tasks are done by different departments of an organization, there has been a significant problem in that the design results have not been made fully available for testing operations.
The present invention is essentially directed to the provision of a useful solution to the inevitable problems noted above. This is achieved by having a data diagnosis unit connected operatively to a data processing unit in an attempt to reduce and automate the design and design review jobs, and by making good use of the design data accumulated at the design stage in the testing operations that follow, and by automating the diagnosis of test data obtained, thus contributing to a reduction in the number of steps to be undertaken in the test operations and to a shortening of the period required for testing.